Spicy Tuna Onigiri: the Easy Recipe for a Typical Japanese Main Dish!

Spicy Tuna Onigiri are typical Japanese rice balls, a snack that is always present in the bento of workers and students, or the lunch box. They are small triangles of rice seasoned with rice vinegar, stuffed with various fillings, usually tuna or salmon, and decorated with sesame seeds. The whole thing is completed with a strip of nori seaweed, which allows you to eat the onigiri with your hands without getting dirty: in fact, they are one of the few Japanese dishes that are eaten without chopsticks and without bowls. Alongside onigiri, the bento also features steamed vegetables, tempura or traditional sushi. As often happens in Japanese rice-based dishes, onigiri are accompanied by saké, a sauce that enhances their sweet aftertaste even more.

What is Onigiri?

Onigiri, also known as rice balls, have a rich history in Japan dating back over a thousand years. They were originally created as a portable and convenient food for travelers and soldiers. Made from rice, onigiri can be shaped by hand or with molds and are often wrapped in nori (seaweed) for ease of handling. Traditional fillings include pickled plums (umeboshi), salted salmon, and various other savory ingredients. Spicy tuna onigiri, a modern twist on this classic dish, likely originated from the fusion of traditional Japanese cuisine with international influences, particularly from the popularity of spicy tuna rolls in sushi restaurants. This contemporary version combines the classic rice ball with a flavorful, spicy tuna filling, blending tradition with innovation.

Tips for The Best Spicy Tuna Onigiri

• Wash the sushi rice under running water until the water runs clear. This step removes excess starch, preventing the rice from becoming too sticky and clumpy.
• Ensure you use the correct rice-to-water ratio. For 360g (1 ⅘ cup) of sushi rice, use 840ml (3 ½ cups) of water. Cooking with the right amount of water helps the rice absorb properly, resulting in the perfect texture.
• Allow the seasoned rice to cool slightly before handling. This makes it easier to work with and prevents it from burning your hands.
• Keep a bowl of water nearby to wet your hands while shaping the rice balls. Wet hands prevent the rice from sticking to your fingers, making it easier to form the shapes.
   
• After shaping the sushi triangles, add a piece of nori (seaweed) to help hold the shape and add a traditional sushi flavor. Press the nori firmly against the rice to ensure it sticks.

What's The Best Rice to Use for Onigiri?

The most suitable rice for preparing onigiri is kome rice or glutinous rice, characterized by small, round grains that remain firm and sticky during cooking. As a substitute for sushi rice, you can use Originario rice or Roma rice.

Which Canned Tuna is Best for Onigiri?

The best type of canned tuna for these onigiri is solid white albacore tuna, packed in water. It has a firm texture and mild flavor that works well with the other ingredients.

Can I Add Other Spices and Sauces for the Filling?

Absolutely! Soy sauce, sriracha, or teriyaki sauce can enhance the flavor of the tuna and avocado mixture. Adjust to your taste preference.

What If I Don't Want Them to Be Spicy?

Yes, you can omit the hot sauce from the filling if you prefer a milder flavor. The onigiri will still be delicious without it.

Can I Make Another Type of Filling?

You can make onigiri with the filling you prefer, using smoked salmon, raw fish – frozen before use – but also chicken or vegetables and serve them with wasabi or teriyaki sauce.

Can I Make These Ahead?

You can prepare sushi rice in advance, in the morning or the day before. If you will use it after a few hours, leave it covered with a damp cloth. If, however, you want to use it the next day, let it cool and store it in the refrigerator. Take it out at least a couple of hours before using it, as it will need to be at room temperature.

Can I Use a Mold to Shape the Onigiri?

Yes, certainly! They make the process easier and ensure consistent shapes.

Can I Freeze Onigiri?

It's not recommended! It's best to not freeze cooked rice, as it tends to become grainy, crumbly and dry once it gets thawed.

Are Onigiri Eaten Hot or Cold?

Onigiri can be eaten either hot or cold. They are traditionally enjoyed at room temperature, making them convenient for packed lunches and picnics.

How Do I Keep My Onigiri From Getting Soggy?

To keep onigiri from getting soggy, wrap them individually in plastic wrap or store them in an airtight container. Additionally, keep the nori (seaweed) separate and wrap it around the onigiri just before eating.

More Japanese Recipes To Try!

Japanese Condensed Milk Bread

Tamagoyaki Recipe

Oyakodon Recipe

Homemade Ramen

Miso-Glazed Black Cod

Japanese Cheesecake

How to Store Spicy Tuna Onigiri

Onigiri can be stored in the refrigerator for up to 1 day, tightly closed in an airtight container. We do not recommend freezing.

How to Make Spicy Tuna Onigiri

Wash the sushi rice under running water until the water runs clear.

Cover the sushi rice with water – mind the ratio! – inside of a pan and cook it over medium heat for about 10-12 minutes, or until it has absorbed all the water.

In the meantime prepare the seasoning for the rice: in a small bowl mix the rice vinegar with hot water, sugar and salt.

Pour the seasoning over the rice, together with the black sesame seeds and mix, to combine carefully and evenly. Let the rice cool down slightly.

In another bowl, combine the filling: the drained canned tuna, chopped avocado, mayonnaise and hot sauce, until it has blended together well.

Take a ball of rice, flatten it with your hands, and add a bit of the filling on top of it. Cover with more rice and pinch the rice to close the filling.

Shape it into the traditional triangle and add a nori seaweed on the bottom to close it and make it easier to eat.

Place on a platter.

Enjoy!